Spatiotemporal characteristics of the atmospheric AOD in the Gobi desert according to data of the ground-based observations

Abstract

Results of studying the aerosol optical depth (AOD) in the atmosphere of the arid zone of Mongolia are discussed. The sites of the photometric observations were located on the territory of Gobi desert and included the Dalanzadgad, Sainshand, and Baruun-Urt stations. The seasonal and interannual AOD variations were analyzed using data of multiyear observations at the AERONET station in Dalanzadgad for the period from 1997 to 2010. It is found that there is, on average, high atmospheric transparency (average AOD in the region of 500 nm is 0.09) with a pronounced annual behavior in the Gobi desert; the maximum is observed in spring and summer months due to the high frequency of occurrence of dust storms in this period, and the minimum is observed in winter months. There is a high proportion of finely dispersed aerosol during summer months compared to other seasons. We analyzed the spectral features of the atmospheric AOD under the conditions of dust outbreaks and the spatial differences in diverse climatic zones: under the conditions of dry climate of the arid zone of Mongolia and the temperate climatic zone of the Baikal region.